Slipknot bassist is believed to have died of a "drug overdose"

The heavy metal musician`s body was found on 24.05.10 in a room at the Town Plaza Hotel, in Des Moines, Iowa, by staff member Mike Kellow who immediately dialled 911.

Audio footage of the call includes Kellow saying: "We believe that it`s a drug overdose. There`s a hypodermic needle next to his bed here."

Asked if Gray was awake, the worker replies: "Oh God, no."

He then explains it appeared as though Gray had been dead "for a while".

Authorities reported that no signs of foul play or significant trauma were found during the autopsy, with the cause of death expected to be revealed when toxicology results come back in the next six weeks.

Following Gray`s death, his Slipknot bandmates paid tribute to him this week - appearing without their infamous stage masks as a mark of respect.

Drummer Shawn Crahan said: "Paul Gray was the essence of the band Slipknot. Paul was there from the very beginning and none of us would be on the path we`re on right now in life or have the sorts of lives we have without him.

"He is going to be sadly missed and the world is going to be a different place without him."